This chapter describes the formats for data files that can be imported into OpenSim. Generally, you must input the following types of data into OpenSim to generate simulations:

Marker trajectories

Ground reaction forces and moments and centers of pressure

You may also import joint angles to provide additional kinematic data. Marker trajectories must be specified in .trc files, and ground reaction and center of pressure data must be specified in .sto or .mot files. Joint angles must be specified in .sto or .mot files. The .sto file format, which is similar to the .mot file format, is described below. EMG data may also be imported using .sto or .mot files, for example, to compare experimental EMG data to muscle excitations obtained from a simulation. This section covers: